1. Field of the Invention
The present invention relates to an opto-electric device.
The present invention further relates to a method for manufacturing an opto-electric device.
2. Related Art
WO/2011/108921 discloses an opto-electrical device that comprises a cover, a barrier structure, an opto-electrical structure and a plurality of transverse electrical conductors. Therein the cover includes a metal foil and a patterned electrically conductive layer carried by and electrically insulated from the metal foil. The opto-electrical structure is sandwiched between the cover and the barrier structure. The opto-electrical structure comprises at least an opto-electrical layer and a transparent electrically conductive layer. The opto-electrical structure has a first main surface facing towards the cover. The plurality of transverse electrical conductors extend from the metal foil or the patterned electrically conductive layer of the cover through the at least one opto-electrical layer to said transparent electrically conductive layer. The cover extends beyond the first main surface of the opto-electrical structure. In a large area opto-electric device the transverse electrical conductors provide for a regular distribution of the voltage over the surface of the transparent electrically conductive layer. Therewith a homogeneous illumination can be achieved. In a large area photovoltaic device this construction reduces the resistive losses.
The poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT/PSS) dispersion is today the most promising and most widely used hole injecting material in OLED research and development.
PEDOT/PSS is commercially available in a number of grades as a dispersion in water (typically at 1-3% wt. solids). However, the dispersion has several drawbacks. The dispersion is very acidic because of the high loading of PSS in its acidic form. This can cause problems during application, and does not wet organic substrates without a high loading of binders or complex formulation. Unfortunately, binders decrease the conductivity of the resulting film. Moreover, many electronic applications cannot tolerate the presence of water.
An important drawback of using the PEDOT/PSS dispersion directly on a metal substrate is rapid degradation of devices, most likely due to metal migration between the metal substrate and the top electrode which is catalysed by the presence of the PEDOT. It is known for OLEDs to use a conductive metal oxide layer, e.g. indium tin oxide (ITO) as an intermediate layer between the OLED layers and a metal substrate in order to prevent such undesirable interactions whilst allowing the high conductivity of the metal substrate to provide for a regular distribution of the voltage. However, such metal oxides are brittle, expensive and need to be deposited in a vacuum. In particular for roll to roll manufacturing of flexible opto-electrical products this is a substantial disadvantage.
It is an object of the present invention to provide for an opto-electric device that allows the use of PEDOT, while avoiding the above-mentioned problems.
It is a further object of the invention for a method of manufacturing such an opto-electric device.